Aggregation functions

aggregate(collection, func[, points])	Takes a collection of Stairs instances and returns a single instance representing the aggregation.
mean(collection)	Takes a collection of Stairs instances and returns the mean of the corresponding step functions.
median(collection)	Takes a collection of Stairs instances and returns the median of the corresponding step functions.
min(collection)	Takes a collection of Stairs instances and returns the minimum of the corresponding step functions.
max(collection)	Takes a collection of Stairs instances and returns the maximum of the corresponding step functions.

Collection functions

sample(collection[, points, how, expand_key])

Takes a dict-like collection of Stairs instances and evaluates their values across a common set of points.